This invention relates in general to a method or system for controlling the compaction pressure within a ramtube type of refuse compacter and more specifically to a system for automatically controlling the restrictors in apparatus which is capable of compacting refuse and forming coherent pellets therefrom, in response to changes in the pressure within said apparatus.
During the past several years considerable effort has gone into developing new technology for disposing of solid refuse in an environmentally acceptable manner and at the same time recovering, insofar as possible, the useful resources contained therein. One such process is described in U.S. Pat. No. 3,729,298 wherein solid refuse is fed into a vertical shaft furnace in which the combustible portion of the refuse is pyrolized - principally to a fuel gas consisting of carbon monoxide and hydrogen - and in which the uncombustible portion of the refuse is fluidized to molten metal and slag. An improvement on the process described in the above mentioned U.S. patent is described and claimed by J. E. Anderson in U.S. patent application Ser. No. 675,935, filed Apr. 12, 1976. The latter process requires that the refuse be compacted into strong, coherent pellets before being fed into the furnace.
In my U.S. application Ser. No. 675,934, filed Apr. 12, 1976, the entire disclosure of which is incorporated herein by reference, I have described and claimed a device for compacting refuse into pellets suitable for being fed into such furnace and for being used in said improved process. In summary, that device comprises:
(A) A CYLINDRICAL TUBE HAVING AN INLET END AND A DISCHARGE END, A FEED PORT IN THE SIDE WALL OF THE TUBE NEAR THE INLET END THEREOF, THE OPEN DISCHARGE END OF SAID TUBE CONSTITUTING THE DISCHARGE PORT, AND HAVING A COMPACTED REFUSE CHAMBER WHOSE LENGTH IS SHORTER THAN THE SHORTEST CRITICAL LENGTH FOR THE REFUSE TO BE PELLETIZED,
(B) A FEED HOPPER FOR THE REFUSE TO BE COMPACTED HAVING AN OUTLET PORT COMMUNICATING WITH THE INLET PORT OF SAID TUBE,
(C) A RECIPROCATING DRIVEN RAM LOCATED IN THE INLET END OF SAID TUBE AND AXIALLY ALIGNED THEREWITH, THE PERIMETER OF SAID RAM BEING IN SLIDING CONTACT WITH THE INNER SURFACE OF SAID TUBE, AND CAPABLE OF EXERTING A PRESSURE OF AT LEAST 200 PSI ON EACH FORWARD STROKE OF THE RAM, AND
(D) MEANS FOR RESTRICTING THE FLOW OF REFUSE THROUGH SAID TUBE, SAID THAT THE DEGREE OF RESTRICTION IS VARIABLE IN RESPONSE TO CHANGES IN THE FORCE REQUIRED TO ADVANCE THE COLUMN OF COMPACTED REFUSE THROUGH THE TUBE.
The preferred structure of said restricting means comprises a plurality of axially elongated leaves, each of which constitutes a flush section of tube wall, flexibly attached at its upstream end to the tube, movable radially inward or outward of the tube axis at its downstream end, and having edge surfaces parallel to each other. A preferred embodiment of the invention comprises two parallel cylindrical tubes whose respective feed ports communicate with a single feed hopper, wherein the respective rams within each tube operate in tandem such that when one is retracted the other is extended.